You're right, there's really not a way, seeing as in general, all PC audio is going to be rerouted one way or the other.
My setup is as follows (Incase this helps anyone out)
PC and Behringer zmix802 mixer *about 60 USD)
Mic in channel 1.
channel 2 is empty but will use for guitar or drums or whatever.
PC in channel 3
Audio interface in channel 4
Phone in Aux Return
The main outputs are going to whatever speakers I want, and the aux send is going to the PC for returning audio to the PC, with the input mute, so I don't hear echos.
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If the phone is needed in the mix, I will put it in channel 2, and if I need stereo sent back to the PC, I will send the RCA output to the PC instead of the aux send.
A better mixer with a control room out or a subgroup stereo out would be better, but this works for me.
Not trying to hijack the thread, just thought I'd toss this out there incase this ends up helping someone.
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